High flow liquid crystalline polymer composition

ABSTRACT

A liquid crystalline polymer composition that contains a liquid crystalline polymer and an aromatic amide oligomer is provided. The oligomer can serve as a flow aid by altering intermolecular polymer chain interactions, thereby lowering the overall viscosity of the polymer matrix under shear. The oligomer is also not easily volatized or decomposed during compounding, molding, and/or use, which minimizes off-gassing and the formation of blisters that would otherwise impact the final mechanical properties of a part made from the polymer composition. While providing the benefits noted, the aromatic amide oligomer does not generally react with the polymer backbone of the liquid crystalline polymer to any appreciable extent so that the mechanical properties of the polymer are not adversely impacted.

RELATED APPLICATIONS

The present application claims priority to U.S. provisional applicationSer. Nos. 61/528,398, filed on Aug. 29, 2011, and 61/664,850, filed onJun. 27, 2012, which are incorporated herein in their entirety byreference thereto.

BACKGROUND OF THE INVENTION

Electrical components (e.g., fine pitch connectors) are commonlyproduced from thermotropic liquid crystalline polymers (“LCPs”). Onebenefit of such polymers is that they can exhibit a relatively high“flow”, which refers to the ability of the polymer when heated undershear to uniformly fill complex parts at fast rates without excessiveflashing or other detrimental processing issues. In addition to enablingcomplex part geometries, high polymer flow can also enhance the ultimateperformance of the molded component. Most-notably, parts generated fromwell-flowing polymers generally display improved dimensional stabilityowing to the lower molded-in stress, which makes the component moreamenable to downstream thermal processes that can be negatively impactedfrom warpage and other polymer stress relaxation processes that occur inless well-molded materials.

Despite their relatively high flow capacity, current commercial LCPsstill fall short of what is needed to meet the increased molding demandsof intricate part designs without significant compromises to the finalproduct performance. In this regard, various attempts have been made toimprove the flow properties of conventional properties by lowering itsmelt viscosity. One approach to a lower melt viscosity has involvedreducing the molecular weight of the polymer. However in general,decreased molecular weight polymers display reduced thermal andmechanical properties as well as poorer blister performance duringlead-free soldering and other fabrication processes. Other approacheshave also been employed that involve the addition of certain compoundsto the polymer during compounding. For example, an oligomeric additivehas been employed that contains carboxyl and hydroxy terminal groups.Such additives, however, particularly when used in relatively highamounts, can result in the formation of volatile products due to theirdecomposition during melt processing and/or use. This may, in turn, leadto the formation of blisters that can adversely impact the thermal andmechanical properties of the polymer and thus limit its use in certainapplications.

As such, a need continues to exist for high flow liquid thermotropiccrystalline polymers with excellent thermo-mechanical properties.

SUMMARY OF THE INVENTION

In accordance with one embodiment of the present invention, athermotropic liquid crystalline polymer composition is disclosed thatcomprises a liquid crystalline polymer and an aromatic amide oligomerhaving the following general formula (I):

wherein,

ring B is a 6-membered aromatic ring wherein 1 to 3 ring carbon atomsare optionally replaced by nitrogen or oxygen, wherein each nitrogen isoptionally oxidized, and wherein ring B may be optionally fused orlinked to a 5- or 6-membered aryl, heteroaryl, cycloalkyl, orheterocyclyl;

R₅ is halo, haloalkyl, alkyl, alkenyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

m is from 0 to 3;

X₁, X₂, and X₃ are independently C(O)HN or NHC(O); and

R₁, R₂, and R₃ are independently selected from aryl, heteroaryl,cycloalkyl, and heterocyclyl.

Other features and aspects of the present invention are set forth ingreater detail below.

BRIEF DESCRIPTION OF THE FIGURES

A full and enabling disclosure of the present invention, including thebest mode thereof to one skilled in the art, is set forth moreparticularly in the remainder of the specification, including referenceto the accompanying figures, in which:

FIG. 1 is the Proton NMR characterization forN1,N3,N5-triphenylbenzene-1,3,5-tricarboxamide (Compound A); and

FIG. 2 is the Proton NMR characterization forN1,N3,N5-tris(4-benzamidophenyl)benzene-1,3,5-tricarboxamide (CompoundB).

DETAILED DESCRIPTION OF REPRESENTATIVE EMBODIMENTS Definitions

It is to be understood that the terminology used herein is for thepurpose of describing particular embodiments only and is not intended tolimit the scope of the present invention.

“Alkyl” refers to monovalent saturated aliphatic hydrocarbyl groupshaving from 1 to 10 carbon atoms and, in some embodiments, from 1 to 6carbon atoms. “C_(x-y)alkyl” refers to alkyl groups having from x to ycarbon atoms. This term includes, by way of example, linear and branchedhydrocarbyl groups such as methyl (CH₃), ethyl (CH₃CH₂), n-propyl(CH₃CH₂CH₂), isopropyl ((CH₃)₂CH), n-butyl (CH₃CH₂CH2CH₂), isobutyl((CH₃)₂CHCH₂), sec-butyl ((CH₃)(CH₃CH₂)CH), t-butyl ((CH₃)₃C), n-pentyl(CH₃CH₂CH₂CH₂CH₂), and neopentyl ((CH₃)₃CCH₂).

“Alkenyl” refers to a linear or branched hydrocarbyl group having from 2to 10 carbon atoms and in some embodiments from 2 to 6 carbon atoms or 2to 4 carbon atoms and having at least 1 site of vinyl unsaturation(>C═C<). For example, (C_(x)-C_(y))alkenyl refers to alkenyl groupshaving from x to y carbon atoms and is meant to include for example,ethenyl, propenyl, 1,3-butadienyl, and so forth.

“Alkynyl” refers to refers to a linear or branched monovalenthydrocarbon radical containing at least one triple bond. The term“alkynyl” may also include those hydrocarbyl groups having other typesof bonds, such as a double bond and a triple bond.

“Aryl” refers to an aromatic group of from 3 to 14 carbon atoms and noring heteroatoms and having a single ring (e.g., phenyl) or multiplecondensed (fused) rings (e.g., naphthyl or anthryl). For multiple ringsystems, including fused, bridged, and spiro ing systems having aromaticand non-aromatic rings that have no ring heteroatoms, the term “Aryl”applies when the point of attachment is at an aromatic carbon atom(e.g., 5,6,7,8 tetrahydronaphthalene-2-yl is an aryl group as its pointof attachment is at the 2-position of the aromatic phenyl ring).

“Cycloalkyl” refers to a saturated or partially saturated cyclic groupof from 3 to 14 carbon atoms and no ring heteroatoms and having a singlering or multiple rings including fused, bridged, and spiro ring systems.For multiple ring systems having aromatic and non-aromatic rings thathave no ring heteroatoms, the term “cycloalkyl” applies when the pointof attachment is at a non-aromatic carbon atom (e.g.5,6,7,8-tetrahydronaphthalene-5-yl). The term “cycloalkyl” includescycloalkenyl groups, such as adamantyl, cyclopropyl, cyclobutyl,cyclopentyl, cyclooctyl, and cyclohexenyl. The term “cycloalkenyl” issometimes employed to refer to a partially saturated cycloalkyl ringhaving at least one site of >C═C< ring unsaturation.

“Halo” or “halogen” refers to fluoro, chloro, bromo, and iodo.

“Haloalkyl” refers to substitution of alkyl groups with 1 to 5 or insome embodiments 1 to 3 halo groups.

“Heteroaryl” refers to an aromatic group of from 1 to 14 carbon atomsand 1 to 6 heteroatoms selected from oxygen, nitrogen, and sulfur andincludes single ring (e.g. imidazolyl) and multiple ring systems (e.g.benzimidazol-2-yl and benzimidazol-6-yl). For multiple ring systems,including fused, bridged, and spiro ring systems having aromatic andnon-aromatic rings, the term “heteroaryl” applies if there is at leastone ring heteroatom and the point of attachment is at an atom of anaromatic ring (e.g. 1,2,3,4-tetrahydroquinolin-6-yl and5,6,7,8-tetrahydroquinolin-3-yl). In some embodiments, the nitrogenand/or the sulfur ring atom(s) of the heteroaryl group are optionallyoxidized to provide for the N oxide (N→O), sulfinyl, or sulfonylmoieties. Examples of heteroaryl groups include, but are not limited to,pyridyl, furanyl, thienyl, thiazolyl, isothiazolyl, triazolyl,imidazolinyl, isoxazolyl, pyrrolyl, pyrazolyl, pyridazinyl, pyrimidinyl,purinyl, phthalazyl, naphthylpryidyl, benzofuranyl,tetrahydrobenzofuranyl, isobenzofuranyl, benzothiazolyl,benzoisothiazolyl, benzotriazolyl, indolyl, isoindolyl, indolizinyl,dihydroindolyl, indazolyl, indolinyl, benzoxazolyl, quinolyl,isoquinolyl, quinolizyl, quianazolyl, quinoxalyl, tetrahydroquinolinyl,isoquinolyl, quinazolinonyl, benzimidazolyl, benzisoxazolyl,benzothienyl, benzopyridazinyl, pteridinyl, carbazolyl, carbolinyl,phenanthridinyl, acridinyl, phenanthrolinyl, phenazinyl, phenoxazinyl,phenothiazinyl, and phthalimidyl.

“Heterocyclic” or “heterocycle” or “heterocycloalkyl” or “heterocyclyl”refers to a saturated or partially saturated cyclic group having from 1to 14 carbon atoms and from 1 to 6 heteroatoms selected from nitrogen,sulfur, or oxygen and includes single ring and multiple ring systemsincluding fused, bridged, and spiro ring systems. For multiple ringsystems having aromatic and/or non-aromatic rings, the terms“heterocyclic”, “heterocycle”, “heterocycloalkyl”, or “heterocyclyl”apply when there is at least one ring heteroatom and the point ofattachment is at an atom of a non-aromatic ring (e.g.decahydroquinolin-6-yl). In some embodiments, the nitrogen and/or sulfuratom(s) of the heterocyclic group are optionally oxidized to provide forthe N oxide, sulfinyl, sulfonyl moieties. Examples of heterocyclylgroups include, but are not limited to, azetidinyl, tetrahydropyranyl,piperidinyl, N-methylpiperidin-3-yl, piperazinyl,N-methylpyrrolidin-3-yl, 3-pyrrolidinyl, 2-pyrrolidon-1-yl, morpholinyl,thiomorpholinyl, imidazolidinyl, and pyrrolidinyl.

It should be understood that the aforementioned definitions encompassunsubstituted groups, as well as groups substituted with one or moreother functional groups as is known in the art. For example, an aryl,heteroaryl, cycloalkyl, or heterocyclyl group may be substituted withfrom 1 to 8, in some embodiments from 1 to 5, in some embodiments from 1to 3, and in some embodiments, from 1 to 2 substituents selected fromalkyl, alkenyl, alkynyl, alkoxy, acyl, acylamino, acyloxy, amino,quaternary amino, amide, imino, amidino, aminocarbonylamino,amidinocarbonylamino, aminothiocarbonyl, aminocarbonylamino,aminothiocarbonylamino, aminocarbonyloxy, aminosulfonyl,aminosulfonyloxy, aminosulfonylamino, aryl, aryloxy, arylthio, azido,carboxyl, carboxyl ester, (carboxyl ester)amino, (carboxyl ester)oxy,cyano, cycloalkyl, cycloalkyloxy, cycloalkylthio, guanidino, halo,haloalkyl, haloalkoxy, hydroxy, hydroxyamino, alkoxyamino, hydrazino,heteroaryl, heteroaryloxy, heteroarylthio, heterocyclyl,heterocyclyloxy, heterocyclylthio, nitro, oxo, thione, phosphate,phosphonate, phosphinate, phosphonamidate, phosphorodiamidate,phosphoramidate monoester, cyclic phosphoramidate, cyclicphosphorodiamidate, phosphoramidate diester, sulfate, sultanate,sulfonyl, substituted sulfonyl, sulfonyloxy, thioacyl, thiocyanate,thiol, alkylthio, etc., as well as combinations of such substituents.

“Liquid crystalline polymer” or “liquid crystal polymer” refers to apolymer that can possess a rod-like structure that allows it to exhibitliquid crystalline behavior in its molten state (e.g., thermotropicnematic state). The polymer may contain aromatic units (e.g., aromaticpolyesters, aromatic polyesteramides, etc.) so that it is whollyaromatic (e.g., containing only aromatic units) or partially aromatic(e.g., containing aromatic units and other units, such as cycloaliphaticunits). The polymer may also be fully crystalline or semi-crystalline innature.

DETAILED DESCRIPTION

It is to be understood by one of ordinary skill in the art that thepresent discussion is a description of exemplary embodiments only, andis not intended as limiting the broader aspects of the presentinvention.

Generally speaking, the present invention is directed to a liquidcrystalline polymer composition that contains a thermotropic liquidcrystalline polymer and an aromatic amide oligomer that can serve as aflow aid by altering intermolecular polymer chain interactions, therebylowering the overall viscosity of the polymer matrix under shear. Inaddition to simply reducing viscosity, the present inventors have alsodiscovered that the oligomer is not easily volatized or decomposedduring compounding, molding, and/or use. This minimizes off-gassing andthe formation of blisters that would otherwise impact the finalmechanical properties of a part made from the polymer composition.Without intending to be limited by theory, it is believed that activehydrogen atoms of the amide functional groups are capable of forming ahydrogen bond with the backbone of liquid crystalline polyesters orpolyesteramides. Such hydrogen bonding strengthens the attachment of theoligomer to the liquid crystalline polymer matrix and thus minimizes thelikelihood that it becomes volatilized during formation. While providingthe benefits noted, the aromatic amide oligomer does not generally reactwith the polymer backbone of the liquid crystalline polymer to anyappreciable extent so that the mechanical properties of the polymer arenot adversely impacted.

The aromatic amide oligomer generally has a relatively low molecularweight so that it can effectively serve as a flow aid for the polymercomposition. For example, the oligomer typically has a molecular weightof about 3,000 grams per mole or less, in some embodiments from about100 to about 2,000 grams per mole, in some embodiments from about 200 toabout 1,500 grams per mole, and in some embodiments, from about 300 toabout 1,200 grams per mole. In addition to possessing a relatively lowmolecular weight, the oligomer also generally possesses a high amidefunctionality so it is capable of undergoing a sufficient degree ofhydrogen bonding with the liquid crystalline polymer. The degree ofamide functionality for a given molecule may be characterized by its“amide equivalent weight”, which reflects the amount of a compound thatcontains one molecule of an amide functional group and may be calculatedby dividing the molecular weight of the compound by the number of amidegroups in the molecule. For example, the aromatic amide oligomer maycontain from 3 to 15, in some embodiments from 3 to 12, and in someembodiments, from 3 to 8 amide functional groups per molecule. The amideequivalent weight may likewise be from about 10 to about 1,000 grams permole or less, in some embodiments from about 50 to about 500 grams permole, and in some embodiments, from about 100 to about 300 grams permole.

As indicated above, it is desirable that the amide oligomerfunctionality is also generally unreactive so that it does not formcovalent bonds with the liquid crystalline polymer backbone. To helpbetter minimize reactivity, the oligomer typically contains a coreformed from one or more aromatic rings (including heteroaromatic). Theoligomer may also contain terminal groups formed from one or morearomatic rings and/or cycloalkyl groups. Such an “aromatic” oligomerthus possesses little, if any, reactivity with the base liquidcrystalline polymer. For example, the aromatic amide oligomer may havethe following general Formula (I):

wherein,

ring B is a 6-membered aromatic ring wherein 1 to 3 ring carbon atomsare optionally replaced by nitrogen or oxygen, wherein each nitrogen isoptionally oxidized, and wherein ring B may be optionally fused orlinked to a 5- or 6-membered aryl, heteroaryl, cycloalkyl, orheterocyclyl;

R₅ is halo, haloalkyl, alkyl, alkenyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl;

m is from 0 to 3;

X₁, X₂, and X₃ are independently C(O)HN or NHC(O);

R₁, R₂, and R₃ are independently selected from aryl, heteroaryl,cycloalkyl, and heterocyclyl.

Another embodiment of such a compound is provided by general formula(II):

wherein,

ring B, R₅, X₁, X₂, X₃, R₁, R₂, and R₃ are as defined above;

X₄ is C(O)HN or NHC(O); and

R₄ is selected from aryl, heteroaryl, cycloalkyl, and heterocyclyl.

Furthermore, in certain embodiments, Ring B may be selected from thefollowing:

wherein,

m is 0, 1, 2, or 3, in some embodiments m is 0, 1, or 2, in someembodiments m is 0 or 1, and in some embodiments, m is 0; and

R₅ is halo, haloalkyl, alkyl, alkenyl, aryl, heteroaryl, cycloalkyl, orheterocyclyl. Ring B may be phenyl.

In some embodiments, R₁, R₂, R₃, and/or R₄ may be selected from thefollowing:

wherein,

n is 0, 1, 2, 3, 4, or 5, in some embodiments n is 0, 1, or 2, and insome embodiments, n is 0 or 1; and

R₆ is halo, haloalkyl, alkyl, alkenyl, alkynyl, aryl, heteroaryl,cycloalkyl, or heterocyclyl.

In one particular embodiment, the aromatic amide oligomer has thefollowing general formula (III):

wherein,

X₁, X₂, and X₃ are independently C(O)HN or NHC(O);

R₅, R₇, R₈, and R₉ are independently selected from halo, haloalkyl,alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl;

m is from 0 to 3; and

p, q, and r are independently from 0 to 5.

In yet another embodiment, the aromatic amide oligomer has the followinggeneral formula (IV):

wherein,

X₁, X₂, X₃, R₅, R₇, R₈, R₉, m, p, q, and r are as defined above.

For example, in certain embodiments, m, p, q, and r in Formula (III) orin Formula (IV) may be equal to 0 so that the core and terminal aromaticgroups are unsubstituted. In other embodiments, m may be 0 and p, q, andr may be from 1 to 5. In such embodiments, for example, R₇, R₈, and/orR₉ may be halo (e.g., fluorine). In other embodiments, R₇, R₈, and/or R₉may be aryl (e.g., phenyl), cycloalkyl (e.g., cyclohexyl), or aryland/or cycloalkyl substituted with an amide group having the structure:—C(O)R₁₂N— or —NR₁₃C(O)—, wherein R₁₂ and R₁₃ are independently selectedfrom hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkyl,and heterocyclyl. In one particular embodiment, for example, R₇, R₈,and/or R₉ are phenyl substituted with —C(O)HN— or —NHC(O)—. In yet otherembodiments, R₇, R₈, and/or R₉ may be heteroaryl (e.g., pyridinyl).

Specific embodiments of the aromatic amide oligomer of the presentinvention are also set forth in the table below:

Cmpd # Structure Name A

N1,N3,N5-triphenylbenzene-1,3,5- tricarboxamide B

N1,N3,N5-tris(4- benzamidophenyl)benzene- 1,3,5-tricarboxamide C

N-(4,6-dibenzamido-1,3,5-triazin-2- yl)benzamide D

N1,N3,N5-tris(3- benzamidophenyl)benzene-1,3,5- tricarboxamide

Generally speaking, the aromatic amide oligomer of the present inventionmay be employed in conjunction with any of a variety of knownthermotropic liquid crystalline polymers. Suitable liquid crystallinepolymers are generally condensation polymers that have relatively rigidand linear polymer chains so that they melt to form a liquid crystallinephase. Examples of such polymers may include, for instance, aromaticpolyesters, aromatic poly(esteramides), aromatic poly(estercarbonates),aromatic polyamides, etc. Such polymers may, for example, containrepeating units formed from one or more aromatic or aliphatichydroxycarboxylic acids, aromatic or aliphatic dicarboxylic acids,aromatic or aliphatic diols, aromatic or aliphatic aminocarboxylicacids, aromatic or aliphatic amines, aromatic or aliphatic diamines,etc., as well as combinations thereof.

Particularly suitable aromatic polyesters are obtained by polymerizing(1) two or more aromatic hydroxycarboxylic acids; (2) at least onearomatic hydroxycarboxylic acid, at least one aromatic dicarboxylicacid, and at least one aromatic diol; and/or (3) at least one aromaticdicarboxylic acid and at least one aromatic diol. Examples of suitablearomatic hydroxycarboxylic acids include, 4-hydroxybenzoic acid;4-hydroxy-4′-biphenylcarboxylic acid; 2-hydroxy-6-naphthoic acid;2-hydroxy-5-naphthoic acid; 3-hydroxy-2-naphthoic acid;2-hydroxy-3-naphthoic acid; 4′-hydroxyphenyl-4-benzoic acid;3′-hydroxyphenyl-4-benzoic acid; 4′-hydroxyphenyl-3-benzoic acid, etc.,as well as alkyl, alkoxy, aryl and halogen substituents thereof.Examples of suitable aromatic dicarboxylic acids include terephthalicacid; isophthalic acid; 2,6-naphthalenedicarboxylic acid; diphenylether-4,4′-dicarboxylic acid; 1,6-naphthalenedicarboxylic acid;2,7-naphthalenedicarboxylic acid; 4,4′-dicarboxybiphenyl;bis(4-carboxyphenyl)ether; bis(4-carboxyphenyl)butane;bis(4-carboxyphenyl)ethane; bis(3-carboxyphenyl)ether;bis(3-carboxyphenyl)ethane, etc., as well as alkyl, alkoxy, aryl andhalogen substituents thereof. Examples of suitable aromatic diolsinclude hydroquinone; resorcinol; 2,6-dihydroxynaphthaiene;2,7-dihydroxynaphthalene; 1,6-dihydroxynaphthalene,4,4′-dihydroxybiphenyl; 3,3′-dihydroxybiphenyl; 3,4′-dihydroxybiphenyl;4,4′-dihydroxybiphenyl ether; bis(4-hydroxyphenyl)ethane, etc., as wellas alkyl, alkoxy, aryl and halogen substituents thereof. In oneparticular embodiment, the aromatic polyester contains monomer repeatunits derived from 4-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid.The monomer units derived from 4-hydroxybenzoic acid may constitute fromabout 45% to about 85% (e.g., 73%) of the polymer on a mole basis andthe monomer units derived from 2,6-hydroxynaphthoic acid may constitutefrom about 15% to about 55% (e.g., 27%) of the polymer on a mole basis.Such aromatic polyesters are commercially available from Ticona, LLCunder the trade designation VECTRA® A. The synthesis and structure ofthese and other aromatic polyesters may be described in more detail inU.S. Pat. Nos. 4,161,470; 4,473,682; 4,522,974; 4,375,530; 4,318,841;4,256,624; 4,219,461; 4,083,829; 4,184,996; 4,279,803; 4,337,190;4,355,134; 4,429,105; 4,393,191; 4,421,908; 4,434,262; and 5,541,240.

Liquid crystalline polyesteramides may also include those obtained bypolymerizing (1) at least one aromatic hydroxycarboxylic acid and atleast one aromatic aminocarboxylic acid; (2) at least one aromatichydroxycarboxylic acid, at least one aromatic dicarboxylic acid, and atleast one aromatic amine and/or diamine optionally having phenolichydroxy groups; and (3) at least one aromatic dicarboxylic acid and atleast one aromatic amine and/or diamine optionally having phenolichydroxy groups. Suitable aromatic amines and diamines may include, forinstance, 3-aminophenol; 4-aminophenol; 1,4-phenylenediamine;1,3-phenylenediamine, etc., as well as alkyl, alkoxy, aryl and halogensubstituents thereof. In one particular embodiment, the aromaticpolyesteramide contains monomer units derived from 2,6-hydroxynaphthoicacid, terephthalic acid, and 4-aminophenol. The monomer units derivedfrom 2,6-hydroxynaphthoic acid may constitute from about 35% to about85% of the polymer on a mole basis (e.g., 60%), the monomer unitsderived from terephthalic acid may constitute from about 5% to about 50%(e.g., 20%) of the polymer on a mole basis, and the monomer unitsderived from 4-aminophenol may constitute from about 5% to about 50%(e.g., 20%) of the polymer on a mole basis. Such aromatic polyesters arecommercially available from Ticona, LLC under the trade designationVECTRA® B. In another embodiment, the aromatic polyesteramide containsmonomer units derived from 2,6-hydroxynaphthoic acid, and4-hydroxybenzoic acid, and 4-aminophenol, as well as other optionalmonomers (e.g., 4,4′-dihydroxybiphenyl and/or terephthalic acid). Thesynthesis and structure of these and other aromatic poly(esteramides)may be described in more detail in U.S. Pat. Nos. 4,339,375; 4,355,132;4,351,917; 4,330,457; 4,351,918; and 5,204,443.

Regardless of their particular monomeric constituents, the liquidcrystalline polymers may be prepared using a variety of knownpolymerization processes. For example, the monomer(s) (e.g., aromatichydroxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol,aromatic amine, aromatic diamine, etc.) may be introduced into a reactorand heated to initiate a polycondensation reaction. If desired, thereaction may also proceed through the acetylation of the monomers as isknown in the art. For instance, one suitable polymerization techniquemay include charging the monomers into a reactor, adding aceticanhydride to acetylize a hydroxyl group of the monomers, and thencarrying out an acetic acid-removing polycondensation reaction. Forexample, an aromatic polyester may be produced by charging4-hydroxybenzoic acid and 2,6-hydroxynaphthoic acid into a reactor undera nitrogen atmosphere, adding acetic anhydride to form an acetoxy underacetic anhydride reflux, then increasing the temperature to carry outacetic acid-removing melt polycondensation while distilling off theacetic acid in a temperature range of 150 to 350° C. If desired, acatalyst can optionally be used in the polymerization reaction, such asmetal salt catalysts (e.g., magnesium acetate, tin(I) acetate,tetrabutyl titanate, lead acetate, sodium acetate, potassium acetate,etc.) and organic compound catalysts (e.g., N-methylimidazole). Suchcatalysts are typically used in amounts of from about 50 to about 500parts per million based on the total weight of the recurring unitprecursors. The particular conditions and steps employed in suchreactions are well known, and may be described in more detail in U.S.Pat. No. 4,161,470 to Calundann and U.S. Pat. No. 6,514,611 to Shepherd,et al.

Polymerization may be carried by melt polymerization or a two-steppolymerization method that includes melt polymerization and solid phasepolymerization. When carrying out solid-phase polymerization on apolymer obtained by melt polymerization, it is typically desired toselect a method in which the polymer obtained by melt polymerization issolidified and then pulverized to form a powdery or flake-like polymer,followed by performing solid polymerization method, such as a heattreatment in a temperature range of 200 to 350° C. under an inertatmosphere (e.g., nitrogen). The solid-phase polymerization may becarried out while stirring or in a still state without any stirring. Thepolymerization reaction apparatus is not especially limited, although itis typically desired to employ one that is commonly used in reactions ofhigh viscosity fluids. Examples of such a reaction apparatus may includea stirring tank type polymerization reaction apparatus having a stirringdevice that has a variously shaped stirring blade, such as an anchortype, a multistage type, a spiral-ribbon type, a screw shaft type andthe like, or a modified shape thereof. Further examples of such areaction apparatus include a mixing apparatus commonly used in resinkneading, such as a kneader, a roll mill, a Banbury mixer, etc.Following polymerization, the molten polymer may be discharged from thereactor, typically through an extrusion orifice fitted with a die ofdesired configuration, cooled, and collected. Commonly, the melt isdischarged through a perforated die to form strands that are taken up ina water bath, pelletized and dried. The resin may also be in the form ofa strand, granule, or powder.

Regardless of the manner in which it is formed, the resulting liquidcrystalline polymer typically has a number average molecular weight(M_(n)) of about 2,000 grams per mole or more, in some embodiments fromabout 4,000 grams per mole or more, and in some embodiments, from about5,000 to about 30,000 grams per mole. To achieve such molecular weights,the addition of a small amount of an end-capping monomer unit or aslight imbalance in stoichiometry may be employed. For example, a smallamount of terephthalic acid may sometimes be included in polymersderived from 2,6-hydroxynaphthoic acid and 4-hydroxybenzoic acid toachieve a molecular weight within the desired range. Of course, it isalso possible to form polymers having a lower molecular weight, such asless than about 2,000 grams per mole, using the method of the presentinvention. The intrinsic viscosity of the polymer composition, which isgenerally proportional to molecular weight, may likewise be about 2deciliters per gram (“dL/g”) or more, in some embodiments about 3 dL/gor more, in some embodiments from about 4 to about 20 dL/g, and in someembodiments from about 5 to about 15 dig. Intrinsic viscosity may bedetermined in accordance with ISO-1628-5 using a 50/50 (v/v) mixture ofpentafluorophenol and hexafluoroisopropanol, as described in more detailbelow.

The relative proportion of the liquid crystalline polymer and thearomatic amide oligomer in the composition may be selected to helpachieve a balance between viscosity and mechanical properties. Moreparticularly, high oligomer contents can result in low viscosity, buttoo high of a content may reduce the viscosity to such an extent thatthe oligomer adversely impacts the melt strength of the polymer blend.In most embodiments, for example, the aromatic amide oligomer isemployed in an amount of from about 0.1 to about 5 parts, in someembodiments from about 0.2 to about 4 parts, and in some embodiments,from about 0.3 to about 1.5 parts by weight relative to 100 parts byweight of the liquid crystalline polymer. The aromatic amide oligomersmay, for example, constitute from about 0.1 wt. % to about 5 wt. %, insome embodiments from about 0.2 wt. % to about 4 wt %, and in someembodiments, from about 0.3 wt. % to about 1.5 wt. % of the polymercomposition. Liquid crystalline polymers may likewise constitute fromabout 95 wt. % to about 99.9 wt. %, in some embodiments from about 96wt. % to about 98.8 wt. %, and in some embodiments, from about 98.5 wt.% to about 99.7 wt. % of the polymer composition.

The manner in which the oligomer and the liquid crystalline polymer arecombined may vary as is known in the art. For instance, the rawmaterials may be supplied either simultaneously or in sequence to a meltprocessing device that dispersively blends the materials. Batch and/orcontinuous melt processing techniques may be employed. For example, amixer/kneader, Banbury mixer, Farrel continuous mixer, single-screwextruder, twin-screw extruder, roll mill, etc., may be utilized to blendand melt process the materials. One particularly suitable meltprocessing device is a co-rotating, twin-screw extruder (e.g., Leistritzco-rotating fully intermeshing twin screw extruder). Such extruders mayinclude feeding and venting ports and provide high intensitydistributive and dispersive mixing. For example, the liquid crystallinepolymer and oligomer may be fed to the same or different feeding portsof a twin-screw extruder and melt blended to form a substantiallyhomogeneous melted mixture. Melt blending may occur under highshear/pressure and heat to ensure sufficient dispersion. For example,melt processing may occur at a temperature of from about 50° C. to about500° C., and in some embodiments, from about 100° C. to about 250° C.Likewise, the apparent shear rate during melt processing may range fromabout 100 seconds⁻¹ to about 10,000 seconds⁻¹, and in some embodiments,from about 500 seconds⁻¹ to about 1,500 seconds⁻¹. Of course, othervariables, such as the residence time during melt processing, which isinversely proportional to throughput rate, may also be controlled toachieve the desired degree of homogeneity.

Besides melt blending, other techniques may also be employed to combinethe oligomer and the liquid crystalline polymer. For example, theoligomer may be supplied during one or more stages of the polymerizationof the liquid crystalline polymer. For example, the aromatic amideoligomer may also be added to the polymerization apparatus. Although itmay be introduced at any time, it is typically desired to apply theoligomer before melt polymerization has been initiated, and typically inconjunction with the precursor monomers for the liquid crystallinepolymer. The reaction mixture is generally heated to an elevatedtemperature within the polymerization reactor vessel to initiate meltpolycondensation of the reactants, Polycondensation may occur, forinstance, within a temperature range of from about 210° C. to about 400°C., and in some embodiments, from about 250° C. to about 350° C. Forinstance, one suitable technique for forming an aromatic polyester mayinclude charging precursor monomers (e.g., 4-hydroxybenzoic acid and2,6-hydroxynaphthoic acid), aromatic amide oligomer, and aceticanhydride into the reactor, heating the mixture to a temperature of fromabout 90° C. to about 150° C. to acetylize a hydroxyl group of themonomers (e.g., forming acetoxy), and then increasing the temperature toa temperature of from about 210° C. to about 400° C. to carry out meltpolycondensation. As the final polymerization temperatures areapproached, volatile byproducts of the reaction (e.g., acetic acid) mayalso be removed so that the desired molecular weight may be readilyachieved. The reaction mixture is generally subjected to agitationduring polymerization to ensure good heat and mass transfer, and inturn, good material homogeneity. The rotational velocity of the agitatormay vary during the course of the reaction, but typically ranges fromabout 10 to about 100 revolutions per minute (“rpm”), and in someembodiments, from about 20 to about 80 rpm. To build molecular weight inthe melt, the polymerization reaction may also be conducted undervacuum, the application of which facilitates the removal of volatilesformed during the final stages of polycondensation. The vacuum may becreated by the application of a suctional pressure, such as within therange of from about 5 to about 30 pounds per square inch (“psi”), and insome embodiments, from about 10 to about 20 psi. Following meltpolymerization, the molten polymer may be discharged from the reactor,typically through an extrusion orifice fitted with a die of desiredconfiguration, cooled, and collected. Commonly, the melt is dischargedthrough a perforated die to form strands that are taken up in a waterbath, pelletized and dried.

Regardless of the manner in which it is introduced, the aromatic amideoligomer may lower the melt viscosity of the resulting polymercomposition. The melt viscosity may, for instance, be reduced so thatthe ratio of the starting liquid crystalline polymer viscosity to theblended composition viscosity is at least about 1.1, in some embodimentsat least about 1.2, in some embodiments from about 1.5 to about 50, insome embodiments from about 3 to about 40, and in some embodiments, fromabout 5 to about 30. In one particular embodiment, the polymercomposition may have a melt viscosity of from about 0.5 to about 100Pa-s, in some embodiments from about 1 to about 80 Pa-s, and in someembodiments, from about 2 to about 50 Pa-s, determined at a shear rateof 1000 seconds⁻¹. Melt viscosity may be determined in accordance withISO Test No. 11443 (equivalent to ASTM Test No. 1238-70) at atemperature of 350° C.

The melting point of the polymer composition may also range from about250° C. to about 400° C., in some embodiments from about 270° C. toabout 380° C., and in some embodiments, from about 300° C. to about 360°C. Likewise, the crystallization temperature may range from about 200°C. to about 400° C., in some embodiments from about 250° C. to about350° C., and in some embodiments, from about 270° C. to about 320° C.The melting and crystallization temperatures may be determined as iswell known in the art using differential scanning calorimetry (“DSC”),such as determined by ISO Test No. 11357.

If desired, the resulting polymer composition may also be combined witha wide variety of other types of components. For example, a fillermaterial may be incorporated into the polymer composition to form afilled composition and to enhance strength. A filled polymer compositioncan include, for example, a mineral filler and/or a fiber filleroptionally in conjunction with one or more other additives as aregenerally known in the art.

Fibers may be employed as a filler material to improve the mechanicalproperties. Such fibers generally have a high degree of tensile strengthrelative to their mass. For example, the ultimate tensile strength ofthe fibers (determined in accordance with ASTM D2101) is typically fromabout 1,000 to about 15,000 Megapascals (“MPa”), in some embodimentsfrom about 2,000 MPa to about 10,000 MPa, and in some embodiments, fromabout 3,000 MPa to about 6,000 MPa. To help maintain an insulativeproperty, which is often desirable for use in electronic components, thehigh strength fibers may be formed from materials that are alsogenerally insulative in nature, such as glass, ceramics (e.g., aluminaor silica), aramids (e.g., Kevlar® marketed by E. I. duPont de Nemours,Wilmington, Del.), polyolefins, polyesters, etc., as well as mixturesthereof. Glass fibers are particularly suitable, such as E-glass,A-glass, C-glass, D-glass, AR-glass, R-glass, S1-glass, S2-glass, etc.,and mixtures thereof.

The volume average length of the fibers may be from about 50 to about400 micrometers, in some embodiments from about 80 to about 250micrometers, in some embodiments from about 100 to about 200micrometers, and in some embodiments, from about 110 to about 180micrometers. The fibers may also have a narrow length distribution. Thatis, at least about 70% by volume of the fibers, in some embodiments atleast about 80% by volume of the fibers, and in some embodiments, atleast about 90% by volume of the fibers have a length within the rangeof from about 50 to about 400 micrometers, in some embodiments fromabout 80 to about 250 micrometers, in some embodiments from about 100 toabout 200 micrometers, and in some embodiments, from about 110 to about180 micrometers. The fibers may also have a relatively high aspect ratio(average length divided by nominal diameter) to help improve themechanical properties of the resulting polymer composition. For example,the fibers may have an aspect ratio of from about 2 to about 50, in someembodiments from about 4 to about 40, and in some embodiments, fromabout 5 to about 20 are particularly beneficial. The fibers may, forexample, have a nominal diameter of about 10 to about 35 micrometers,and in some embodiments, from about 15 to about 30 micrometers.

The relative amount of the fibers in the filled polymer composition mayalso be selectively controlled to help achieve the desired mechanicalproperties without adversely impacting other properties of thecomposition, such as its flowability. For example, the fibers mayconstitute from about 2 wt. % to about 40 wt. %, in some embodimentsfrom about 5 wt. % to about 35 wt. %, and in some embodiments, fromabout 6 wt. % to about 30 wt. % of the filled polymer composition.Although the fibers may be employed within the ranges noted above, smallfiber contents may be employed while still achieving the desiredmechanical properties. For example, the fibers can be employed in smallamounts such as from about 2 wt. % to about 20 wt. %, in someembodiments, from about 5 wt. % to about 16 wt. %, and in someembodiments, from about 6 wt. % to about 12 wt. %.

When incorporating fibrous fillers into the composition, the fibers canbe introduced to the composition at any time, though it is typicallydesired to introduce the fibers such that the fibers can be welldispersed and distributed throughout the composition. While not wishingto be bound to any particular theory, it is believed that dispersal anddistribution of fibers throughout the composition can be enhanced whenthe polymer melt viscosity is relatively high. Accordingly, in oneembodiment, fibers can be added to the composition prior to addition ofthe aromatic amide oligomer. For instance, a composition formationprocess can include feeding a liquid crystalline polymer to a meltprocessing unit, e.g., an extruder. A fibrous filler can be combinedwith the polymer to form a blend prior to addition of the aromatic amideoligomer, and the blend can be mixed under high shear as is known in theart to disperse and distribute the fibers throughout the molten polymer.

The fibers may generally be added at any location of the melt processingunit. In one embodiment, the fibers may be added at a locationdownstream from the point at which the liquid crystalline polymer issupplied, but yet prior to the melting section. In another embodiment,the fibers may be added at a location downstream from the point at whichthe liquid crystalline polymer becomes molten.

To help encourage dispersion and distribution of the fibers throughoutthe melt, a variety of different parameters may be selectivelycontrolled. For example, the ratio of the length (“L”) to diameter (“D”)of a screw of the melt processing unit may be selected to achieve anoptimum balance between throughput and fiber dispersion anddistribution. For example, the L/D value after the point at which thefibers are supplied may be controlled to encourage dispersion anddistribution of the fibers. More particularly, the screw can have ablending length (“L_(B)”) that is defined from the point at which thefibers are supplied to the unit to the end of the screw, the blendinglength generally being less than the total length of the screw. In oneembodiment, it may be desirable to add the fibers before the liquidcrystalline polymer is melted, which means that the L_(B)/D ratio wouldbe relatively high. However, too high of a L_(B)/D ratio could result indegradation of the polymer. Therefore, the L_(B)/D ratio of the screwafter the point at which the fibers are supplied is typically from about3 to about 20, in some embodiments from about 4 to about 18, and in someembodiments, from about 5 to about 16.

If desired, one or more distributive and/or dispersive mixing elementsmay be employed within the mixing section of the melt processing unit.Suitable distributive mixers for single screw extruders may include, forinstance, Saxon, Dulmage, Cavity Transfer mixers, etc. Likewise,suitable dispersive mixers may include Blister ring, Leroy/Maddock, CRDmixers, etc. As is well known in the art, the mixing may be furtherimproved by using pins in the barrel that create a folding andreorientation of the polymer melt, such as those used in Buss Kneaderextruders, Cavity Transfer mixers, and Vortex Intermeshing Pin mixers.

After thorough mixing of the polymer and the fiber, the aromatic amideoligomer can be added to the melt processing unit, and the compositioncan again be thoroughly mixed to distribute the aromatic amide oligomerthroughout the composition. For instance, the aromatic amide oligomermay be added following the addition of the fibers and at an L_(B)/Dratio of from about 5 to about 25, or from about 8 to about 20.

Following addition of the aromatic amide oligomer, the filledcomposition can be mixed to distribute the aromatic amide oligomerthroughout the composition. The composition may then be passed under avacuum, for instance at an L_(B)/D ratio of between about 30 and about40, the application of which facilitates the removal of volatiles formedduring the final stages of polycondensation and/or during blending ofthe composition. The vacuum may be created by the application of asuctional pressure, such as within the range of from about 5 to about 30pounds per square inch (“psi”), and in some embodiments, from about 10to about 20 psi.

Mineral fillers may be employed as a filler material to improvemechanical properties. Mineral fillers may, for instance, be employed inthe filled polymer composition to help achieve the desired mechanicalproperties and/or appearance. Such fillers are particularly desirablewhen forming thermoformed articles. When employed, mineral fillerstypically constitute from about 5 wt. % to about 60 wt. %, in someembodiments from about 10 wt. % to about 55 wt. %, and in someembodiments, from about 20 wt. % to about 50 wt. % of the polymercomposition. Clay minerals may be particularly suitable for use in thepresent invention. Examples of such clay minerals include, for instance,talc (Mg₃Si₄O₁₀(OH)₂), halloysite (Al₂Si₂O₅(OH)₄), kaolinite(Al₂Si₂O₅(OH)₄), illite ((K,H₃O)(Al,Mg,Fe)₂ (Si,Al)₄O₁₀[(OH)₂,(H₂O)]),montmorillonite (Na,Ca)_(0.33)(Al,Mg)₂Si₄O₁₀(OH)₂.nH₂O), vermiculite((MgFe,Al)₃(Al,Si)₄O₁₀(OH)₂.4H₂O), palygorskite((Mg,Al)₂Si₄O₁₀(OH).4(H₂O)), pyrophyllite (Al₂Si₄O₁₀(OH)₂), etc., aswell as combinations thereof. In lieu of, or in addition to, clayminerals, still other mineral fillers may also be employed. For example,other suitable silicate fillers may also be employed, such as calciumsilicate, aluminum silicate, mica, diatomaceous earth, wollastonite, andso forth. Mica, for instance, may be particularly suitable. There areseveral chemically distinct mica species with considerable variance ingeologic occurrence, but all have essentially the same crystalstructure. As used herein, the term “mica” is meant to genericallyinclude any of these species, such as muscovite (KAl₂(AlSi₃)O₁₀(OH)₂),biotite (K(Mg,Fe)₃(AlSi₃)O₁₀(OH)₂), phlogopite (KMg₃(AlSi₃)O₁₀(OH)₂),lepidolite (K(Li,Al)₂₋₃(AlSi₃)O₁₀(OH)₂), glauconite(K,Na)(Al,Mg,Fe)₂(Si,Al)₄O₁₀(OH)₂), etc., as well as combinationsthereof.

Still other additives that can be included in the filled polymercomposition may include, for instance, antimicrobials, pigments (e.g.,carbon black), antioxidants, stabilizers, surfactants, waxes, solidsolvents, and other materials added to enhance properties andprocessability. Lubricants, for instance, may be employed in the polymercomposition. Examples of such lubricants include fatty acids esters, thesalts thereof, esters, fatty acid amides, organic phosphate esters, andhydrocarbon waxes of the type commonly used as lubricants in theprocessing of engineering plastic materials, including mixtures thereof.Suitable fatty acids typically have a backbone carbon chain of fromabout 12 to about 60 carbon atoms, such as myristic acid, palmitic acid,stearic acid, arachic acid, montanic acid, octadecinic acid, parinricacid, and so forth. Suitable esters include fatty acid esters, fattyalcohol esters, wax esters, glycerol esters, glycol esters and complexesters. Fatty acid amides include fatty primary amides, fatty secondaryamides, methylene and ethylene bisamides and alkanolamides such as, forexample, palmitic acid amide, stearic acid amide, oleic acid amide,N,N′-ethylenebisstearamide and so forth. Also suitable are the metalsalts of fatty acids such as calcium stearate, zinc stearate, magnesiumstearate, and so forth; hydrocarbon waxes, including paraffin waxes,polyolefin and oxidized polyolefin waxes, and microcrystalline waxes.Particularly suitable lubricants are acids, salts, or amides of stearicacid, such as pentaerythritol tetrastearate, calcium stearate, orN,N′-ethylenebisstearamide. When employed, the lubricant(s) typicallyconstitute from about 0.05 wt. % to about 1.5 wt. %, and in someembodiments, from about 0.1 wt. % to about 0.5 wt. % (by weight) of thepolymer composition.

The filled polymer composition can exhibit low melt viscosity, which canenhance processing characteristics and lead to improved productcharacteristics, and can also exhibit excellent mechanicalcharacteristics due to the presence and high distribution of the fillermaterial throughout the composition. For example, a filled compositionmay have a melt viscosity of from about 0.5 to about 25 Pa-s, in someembodiments from about 2 to about 20 Pa-s, as determined at a shear rateof 1000 seconds⁻¹ and may also exhibit excellent strengthcharacteristics. By way of example, a filled composition can have atensile strength of greater than about 150 MPa, or greater than about160 MPa; a tensile elongation of greater than about 1.75%, greater thanabout 1.80%, or greater than about 2.00%; and/or a tensile modulus ofgreater than about 15,000 MPa, or greater than about 16,000. Tensileproperties can be determined according to ISO Test No. 527 (technicallyequivalent to ASTM D638) at a temperature of 23° C. and at a test speedof 5 mm/min. The filled composition can have flexural strength ofgreater than about 225 MPa, or greater than about 230 MPa, and/orflexural modulus of greater than about 16,000 MPa, or greater than about16,500 MPa as determined according to ISO Test No. 178 (technicallyequivalent to ASTM D790) at a temperature of 23° C. The filledcomposition can have a notched Charpy impact strength of greater thanabout 30 kJ/m², or greater than about 35 kJ/m² as determined accordingto ASTM D256, Method B (technically equivalent to ISO 179-1) at 23° C.The filled composition can have a deflection temperature under load(DTUL) of greater than about 260° C., or greater than about 265° C. asmeasured according to ASTM D648-07 (technically equivalent to ISO TestNo. 75-2) at a specified load of 1.8 MPa.

The present invention may be better understood with reference to thefollowing examples.

Test Methods

Melt Viscosity: The melt viscosity (Pa-s) was determined in accordancewith ISO Test No. 11443 at 350° C. and at a shear rate of 400 s⁻¹ and1000 s⁻¹ using a Dynisco 7001 capillary rheometer. The rheometer orifice(die) had a diameter of 1 mm, length of 20 mm, L/D ratio of 20.1, and anentrance angle of 180°. The diameter of the barrel was 9.55 mm±0.005 mmand the length of the rod was 233.4 mm.

Intrinsic Viscosity: The intrinsic viscosity (“IV”) may be measured inaccordance with ISO-1628-5 using a 50/50 (v/v) mixture ofpentafluorophenol and hexafluoroisopropanol. Each sample was prepared induplicate by weighing about 0.02 grams into a 22 mL vial. 10 mL ofpentafluorophenol (“PFP”) was added to each vial and the solvent. Thevials were placed in a heating block set to 80° C. overnight. Thefollowing day 10 mL of hexafluoroisopropanol (“HFIP”) was added to eachvial. The final polymer concentration of each sample was about 0.1%. Thesamples were allowed to cool to room temperature and analyzed using aPolyVisc automatic viscometer.

Melting and Crystallization Temperatures: The melting temperature (“Tm”)and crystallization temperature (“Tc”) were determined by differentialscanning calorimetry (“DSC”) as is known in the art. The meltingtemperature is the differential scanning calorimetry (DSC) peak melttemperature as determined by ISO Test No. 11357. The crystallizationtemperature is determined from the cooling exotherm in the coolingcycle. Under the DSC procedure, samples were heated and cooled at 20° C.per minute as stated in ISO Standard 10350 using DSC measurementsconducted on a TA Q2000 Instrument.

Deflection Under Load Temperature (“DTUL”): The deflection under loadtemperature was determined in accordance with ISO Test No. 75-2(technically equivalent to ASTM D648-07). More particularly, a teststrip sample having a length of 80 mm, thickness of 10 mm, and width of4 mm was subjected to an edgewise three-point bending test in which thespecified load (maximum outer fibers stress) was 1.8 Megapascals. Thespecimen was lowered into a silicone oil bath where the temperature israised at 2° C. per minute until it deflects 0.25 mm (0.32 mm for ISOTest No. 75-2).

Tensile Properties: Tensile properties are tested according to ISO TestNo. 527 (technically equivalent to ASTM D638). Modulus and strengthmeasurements are made on the same test strip sample having a length of80 mm, thickness of 10 mm, and width of 4 mm. The testing temperature is23° C., and the testing speeds are 1 or 5 mm/min.

Flexural Properties: Flexural properties are tested according to ISOTest No. 178 (technically equivalent to ASTM D790). This test isperformed on a 64 mm support span. Tests are run on the center portionsof uncut ISO 3167 multi-purpose bars. The testing temperature is 23° C.and the testing speed is 2 mm/min.

Notched Charpy Impact Strength: Notched Charpy properties are testedaccording to ISO Test No. ISO 179-1) (technically equivalent to ASTMD256, Method B). This test is run using a Type A notch (0.25 mm baseradius) and Type 1 specimen size (length of 80 mm, width of 10 mm, andthickness of 4 mm). Specimens are cut from the center of a multi-purposebar using a single tooth milling machine. The testing temperature is 23°C.

Density: Density was determined according to ISO Test No. 1183(technically equivalent to ASTM D792). The specimen was weighed in airthen weighed when immersed in distilled water at 23° C. using a sinkerand wire to hold the specimen completely submerged as required.

Weldline Strength—LGA: The weidline strength is determined by firstforming an injection molded line grid array (“LGA”) connector (size of49 mm×39 mm×1 mm) from a thermoplastic composition sample as is wellknown in the art. Once formed, the LGA connector is placed on a sampleholder. The center of the connector is then subjected to a tensile forceby a rod moving at a speed of 5.08 millimeters per minute. The peakstress is recorded as an estimate of the weldline strength.

Warpage—LGA: The warpage is determined by first forming an injectionmolded line grid array (“LGA”) connector (size of 49 mm×39 mm×1 mm) froma thermoplastic composition sample as is well known in the art. A Corescoplanarity measuring module, model core9037a, is used to measure thedegree of warpage of the molded part. The test is performed; connectoras molded (unaged), and conditioned in 20 minute temperature cycle thatramps from ambient temperature to 270° C., is maintained for 3 minutesand ramped back to room temperature (aged).

Blister Free Temperature: To test blister resistance, a 127×12.7×0.8 mmtest bar is molded at 5° C. to 10° C. higher than the meltingtemperature of the polymer resin, as determined by DSC. Ten (10) barsare immersed in a silicone oil at a given temperature for 3 minutes,subsequently removed, cooled to ambient conditions, and then inspectedfor blisters (i.e., surface deformations) that may have formed. The testtemperature of the silicone oil begins at 250° C. and is increased at10° C. increments until a blister is observed on one or more of the testbars. The “blister free temperature” for a tested material is defined asthe highest temperature at which all ten (10) bars tested exhibit noblisters. A higher blister free temperature suggests a higher degree ofheat resistance.

Synthesis of N1,N3,N5-triphenylbenzene-1,3,5-tricarboxamide Compound A

The synthesis of Compound A from trimesoyl chloride and aniline may beperformed according to the following scheme:

The experimental set up consisted of a 2 L glass beaker equipped with aglass rod stirrer coupled with an overhead mechanical stirrer. Trimesoylchloride (200 g) was dissolved in dimethyl acetamide (“DMAc”) (1 L) andcooled by an ice bath to 10-20° C. Aniline (421 g) was added drop wiseto a stirred solution of the acid chloride over a period of 1.5 to 2hours. After the addition of the amine was completed, the reactionmixture was stirred additionally for 45 minutes, after which thetemperature was increased to 90° C. for about 1 hour. The mixture wasallowed to rest overnight at room temperature. The product was recoveredby precipitation through the addition of 1.5 L of distilled water, whichwas followed by was vacuum filtration using a filter paper and a Buchnerfunnel. The crude product was washed with acetone (2 L) and then washedagain with hot water (2 L). The product was then air dried over night atroom temperature and then was dried in a vacuum oven 150° C. for 4 to 6hours. The product (250 g) was a white solid, and had a melting point of319.6° C., as determined by differential scanning calorimetry (“DSC”).The Proton NMR characterization for the compound is also shown in FIG.1.

Synthesis ofN1,N3,N5-tris(4-benzamidophenyl)benzene-1,3,5-tricarboxamide Compound B

The synthesis of Compound B from trimesoyl chloride and 4-benzoanilidemay be performed according to the following scheme:

The experimental set up consisted of a 2 L glass beaker equipped with aglass rod stirrer coupled with an overhead mechanical stirrer. Trimesoylchloride (83.37 g) was dissolved in DMAc (1 L) at room temperature.4-aminobenzanilide (200 g) was dissolved in DMAc (1 L). The aminesolution was gradually added to the acid chloride solution over a periodof 15 minutes, and the reaction mixture was then stirred and thetemperature increased to 90° C. for about 3 hours. The mixture wasallowed to rest overnight at room temperature. The product was recoveredby precipitation through the addition of 1.5 L of distilled water, whichwas followed by was vacuum filtration using a filter paper and a Buchnerfunnel. The crude product was then washed with acetone (2 L) and washedagain with hot water (2 L). The product was then air dried over night atroom temperature and then was dried in a vacuum oven 150° C. for 4 to 6hours. The product (291 g) was a bright yellow solid. No melting pointwas detected. The Proton NMR characterization for the compound is shownin FIG. 2.

Synthesis ofN1,N3,N5-tris(3-benzamidophenyl)benzene-1,3,5-tricarboxamide Compound D

The synthesis of Compound D from trimesoyl chloride, benzoyl chlorideand 1,3-phenylene diamine can be performed according to the followingscheme:

The experimental set up consisted of a 1 L glass beaker equipped with aglass rod stirrer coupled with an overhead mechanical stirrer. 1,3phenylene diamine (20 g) was dissolved in warm dimethyl acetamide (200mL) (alternatively N-methylpyrrolidone can also be used) and maintainedat 45° C. Next benzoyl chloride (26.51 g) was slowly added drop wiseover a period of 1.5 to 2 hours, to the amine solution with constantstirring. The rate of addition of the benzoyl chloride was maintainedsuch that the reaction temperature was maintained less than 60° C. Aftercomplete addition of the benzoyl chloride, the reaction mixture wasgradually warmed to 85-90° C. and then allowed to cool to around 45-50°C. At this point, trimesoyl chloride (16.03 g) was gradually added tothe reaction mixture such that the exotherm did not increase thereaction temperature above 60° C. After complete addition of thetrimesoyl chloride, the reaction mixture was allowed to stir foradditional 45 minutes, after which the reaction temperature wasincreased to 90° C. for about 30 minutes and then was cooled to roomtemperature. The mixture was allowed to rest overnight at roomtemperature. The product was recovered by precipitation through theaddition of 1.5 L of distilled water, which was followed by was vacuumfiltration using a filter paper and a Buchner funnel. The crude productwas then washed with acetone (250 mL) and washed again with hot water(500 mL). The product (yield: ca. 90%) was then air dried over night atroom temperature and then was dried in a vacuum oven 150° C. for 4 to 6hours. The product was a pale tan solid.

The Proton NMR characterization was as follows: ¹H NMR (400 MHzD₆-DMSO): 10.68 (s, 3H, CONH), 10.3 (s, 3H, CONH), 8.74 (s, 3H, centralAr), 8.1 (d, 3H, m-phenylene Ar), 7.9 (d, 6H, ortho-ArH), 7.51 (m, 15H,meta-para-ArH and 6H, m-phenylene Ar) and 7.36 (m, 3H, m-phenylene Ar).

EXAMPLE 1

Compounds A and B were synthesized as described above and tested fortheir influence on the melt viscosity of a liquid crystalline polymerthat is commercially available from Ticona, LLC and has the followingmonomer content: 63% 4-hydroxybenzoic acid (“HBA”), 5%2,6-hydroxynaphthoic acid (“HNA”), 16% terephthalic acid (“TA”), 11%4,4′-biphenol (“BP”), and 5% acetaminophen (“APAP”). More particularly,the polymer was heated at 120° C. and powder coated with apentaerythritol tetrastearate (PETS, commercial grade Lonza Glycolube P)at a 0.3 wt. % loading based on the weight of the polymer. The hotpellets were then coated with 2 wt. % (based on polymer weight) of oneof Compounds A and B. A control sample was also formed that employed4,4′-biphenol as a flow additive in an amount of 2 wt. %. The mixtureswere then melt mixed using a Leistritz 18 mm co-rotating fullyintermeshing twin screw extruder having 6 temperature control zones(including at the extrusion die) and an overall L/D of 30. A generalpurpose screw design was used to compound the oligomers into a resinmatrix. All materials were fed to the feed throat in the first barrel bymeans of a volumetric feeder. Materials were melted and mixed thenextruded through a single hole strand die. Material was then quenched ina water bath to solidify and granulated in a pelletizer. The resultantpellets were then dried for 3 hours at 120° C. and scanning shearcapillary melt viscosity measurements were carried out at 350° C. Theresults are set forth below.

Comp. Polymer + Polymer + Compound Compound Polymer + Polymer A BBiphenol Melt Viscosity 253 10.7 3.7 6.4 (1000 s⁻¹) (Pa-s) Ratio ofInitial MV to — 2.4 6.8 4.0 Blend MV (1000⁻¹) Melt Viscosity 33.3 16.05.0 7.6 (400 s⁻¹) (Pa-s) Ratio of Initial MV to — 2.1 6.7 4.4 Blend MV(400⁻¹) Intrinsic Visc. (dL/g) 6.96 6.22 5.43 4.39 Tm (° C.) 336.4 318.1329.0 329.9 Tc (° C.) 289.3 277.9 290.0 310.1

As indicated, a melt viscosity reduction (increase in the flow) ofalmost 85% (ratio of 6.8) was achieved through the oligomers of thepresent invention. To determine if this resulted in a change in themechanical properties, the pellets were also injection molded to obtainspecimen samples for tensile, impact, flexural and heat distortiontemperature measurements. The results are set forth below.

Comp. Polymer + Polymer + Compound Compound Polymer + Polymer A BBiphenol Flexural Modulus 12,500.00 11,900 — 10,950 (MPa) Flexural Break167 160 — 141 Stress (MPa) Flexural Break 3.4 3.5 — 2.6 Strain (%)Tensile Modulus 13,150 12,200 13,400 11,750 (MPa) Tensile Break 152 155146 129 Stress (MPa) Tensile Break 1.74 2.15 1.65 2.15 Strain (%) CharpyNotched 90.9 90.3 65.6 49.2 (kJ/m)

As indicated, excellent mechanical properties were observed for thecompositions of the present invention. Without intending to be limitedby theory, it is believed that a significant reduction in mechanicalproperties did not occur because the oligomers did not react directlywith the polymer backbone to reduce its molecular weight.

EXAMPLE 2

Pellet samples were formed of a solid-state polymerized liquidcrystalline polymer that is commercially available from Ticona LLC andhas the following monomer content: 61% HBA, 3% HNA, 18% TA, 13% BP, and5% APAP. The samples were heated at 120° C. and powder coated with apentaerythritol tetrastearate (PETS, commercial grade Lanza Glycolube P)at a 0.3 wt. % loading based on the polymer. The hot pellets were thencoated with fine powders of Compounds A and B at a 2 wt. % loading basedon the weight of the polymer. A sample with only PETS was also preparedsimilarly for baseline purposes. The samples were thoroughly mixed toevenly coat the pellets with the powder compounds. The mixtures werethen melt mixed using a Leistritz 18 mm co-rotating, fully-intermeshing,twin-screw extruder with an overall L/D of 30 and six temperaturecontrol zones including one at the die. A general purpose screw designwas used to compound the oligomers into a resin matrix. All materialswere fed to the feed throat in the first barrel by means of a volumetricfeeder. Materials were melted and mixed then extruded through a singlehole strand die. The strands were water-quenched in a bath to solidifyand granulated in a pelletizer. All compositions were compounded at arate of 11 pounds per hour, a barrel temperature of 360-370° C., and ascrew speed around 300 rpm. Melt mixing parameters and the resultantscrew torque are provided in the table below.

Sample Control + Control + Compound A Compound B Control (2 wt. %) (2wt. %) Screw speed (rpm) 300 302 301 Throughput rate (lb/hr)  10  10  11Torque (amp) 5-12 8-10 6-8 Barrel Temp Zone 1 (° C.) 177 179 266 BarrelTemp Zone 2 (° C.) 308 310 359 Barrel Temp Zone 3 (° C.) 370 366 367Barrel Temp Zone 4 (° C.) 370 371 369 Barrel Temp Zone 5 (° C.) 370 380369 Die Head Temp (° C.) 380 380 363

All compositions resulted in a decrease in extruder torque as comparedto the control, suggesting that these compositions displayed lowerviscosities at high shear rates. The resultant pellets were then driedfor three hours at 120° C. and melt viscosity measurements were carriedout at 370° C. The thermal properties were then tested as describedabove. The results are set forth below.

Comp. Control + Control + Control Compound A Compound B Melt Viscosity(1000 s⁻¹) (Pa-s) 130.8 28.1 38.6 Ratio of Initial MV to Blend — 4.7 3.4MV (1000⁻¹) Melt Viscosity (400 s⁻¹) (Pa-s) 223.9 41.3 59.1 Ratio ofInitial MV to Blend — 5.4 3.8 MV (400⁻¹) Intrinsic Visc. (dL/g)  10.49.6 9.4 Tm (° C.) 362.7 344.5 355.3 Tc (° C.) 301.7 293.8 315.9

As indicated, Compounds A and B resulted in a decrease in meltviscosity. The pellets were then injection molded to obtain specimensamples for tensile, impact, flexural and deflection temperature underload (DTUL) measurements. All compositions were injection molded at ISO294 conditions. The pellets were dried for 3 hours at 120° C. Theproperties are set forth below.

Comp. Control + Control + Control Compound A Compound B DTUL (° C.)248.4 251.4 258.1 Flexural Modulus (MPa) 12,500 12,950 15,100 FlexuralBreak Stress (MPa) 161.9 160.1 179.94 Flexural Break Strain (%) 3.19 3.53.19 Tensile Modulus (MPa) 10,700 11,550 14,350 Tensile Break Stress(MPa) 117.71 137.30 178.37 Tensile Break Strain (%) 1.62 1.66 1.81Charpy Notched (kJ/m) 74.2 101.6 90.0

As shown in the tables above, remarkable drops of 50-80% were seen inthe melt viscosity (MV) of TLCPs prepared with relatively low levels ofCompounds A and B. Notably, these viscosity reductions did not result ina substantial change in mechanical properties.

EXAMPLE 3

A 2 L flask was charged with HBA (432.3 g), HNA (47 g), TA (134.6 g), BP(104.3 g), APAP (37.8 g), Compound A (19.65 g) and 33 mg of potassiumacetate. The flask next was equipped with C-shaped stirrer, a thermalcouple, a gas inlet, and distillation head. The flask was placed under alow nitrogen purge and acetic anhydride (99.7% assay, 501.5 g) wasadded. The milky-white slurry was agitated at 75 rpm and heated to 140°C. over the course of 95 minutes using a fluidized sand bath. After thistime, the mixture was then gradually heated to 350° C. steadily over 290minutes. Reflux was seen once the reaction exceeded 140° C. and theoverhead temperature increased to approximately 115° C. as acetic acidbyproduct was removed from the system. During the heating, the mixturegrew yellow and slightly more viscous and the vapor temperaturegradually dropped to 90° C. Once the mixture had reached 350° C., thenitrogen flow was stopped. The flask was evacuated below 20 psi and theagitation slowed to 30 rpm over the course of 45 minutes. As the timeunder vacuum progressed, the mixture grew viscous. After 84 minutes, thereaction was stopped, no torque was observed. The reaction was thenstopped by releasing the vacuum and stopping the heat flow to thereactor. The flask was cooled and then polymer was recovered as a solid,dense yellow-brown plug. Sample for analytical testing was obtained bymechanical size reduction.

The thermal properties of the polymers of a control sample and Example 3were tested as described above. The results are set forth below.

MV at MV at Intrinsic 1000 s⁻¹ 400 s⁻¹ Tm Tc Viscosity (Pa * s) (Pa * s)Sample Compound (° C.) (° C.) (dL/g) at 350° C. at 350° C. Control —343.7 290.8 8.5 79.6 129.0 Ex. 3 A 314.2 268.3 2.6 7.2 9.3

As indicated, Compound A resulted in a decrease in melt viscosity.

EXAMPLE 4

A first sample (Sample 1) was formed. A 2 L flask was charged with4-hydroxybenzoic acid (415.7 g), 2,6-hydroxynaphthoic acid (32 g),terephthalic acid (151.2 g), 4,4′-biphenol (122.9 g), acetominophen(37.8 g), and 50 mg of potassium acetate. The flask was equipped withC-shaped stirrer, a thermal couple, a gas inlet, and distillation head.The flask was placed under a low nitrogen purge and acetic anhydride(99.7% assay, 497.6 g) was added. The milky-white slurry was agitated at75 rpm and heated to 140° C. over the course of 95 minutes using afluidized sand bath. After this time, the mixture was then graduallyheated to 360° C. steadily over 300 minutes. Reflux was seen once thereaction exceeded 140° C. and the overhead temperature increased toapproximately 115° C. as acetic acid byproduct was removed from thesystem. During the heating, the mixture grew yellow and slightly moreviscous and the vapor temperature gradually dropped to 90° C. Once themixture had reached 360° C., the nitrogen flow was stopped. The flaskwas evacuated below 20 psi and the agitation slowed to 30 rpm over thecourse of 45 minutes. As the time under vacuum progressed, the mixturegrew viscous. After 72 minutes, the final viscosity target was reachedas gauged by the strain on the agitator motor (torque value of 30units). The reaction was then stopped by releasing the vacuum andstopping the heat flow to the reactor. The flask was cooled and thenpolymer was recovered as a solid, dense yellow-brown plug. Sample foranalytical testing was obtained by mechanical size reduction.

A second sample (Sample 2) was formed as described for Sample 1, exceptthat 19.76 grams of Compound A was also introduced into the reactor. Itwas observed that there were fewer residues in the distillate ascompared to Sample 1. The reaction was stopped after 72 minutes—notorque was observed on the agitator motor.

A third sample (Sample 3) was formed as described for Sample 1, exceptthat 18.7 grams of Compound B was also introduced into the reactor. Itwas observed that there were fewer residues in the distillate ascompared to Sample 1. The reaction was stopped after 72 minutes—a torquevalue of 50 units was observed on the agitator motor.

The thermal properties of the melt polymerized polymers of Samples 1-3were tested as described above. The results are set forth below in thefollowing table.

MV at MV at Tm Tc 1000 s⁻¹ 400 s⁻¹ Sample Additive (° C.) (° C.) IV(dL/g) (Pa * s) (Pa * s) 1 — 361.6 301.8 8.4 75.7 118.2 2 A 322.4 275.13.8 27.7 43.6 3 B 343.0 284.7 5.0 137.8 230.1

EXAMPLE 5

A wholly aromatic liquid crystalline polyester (available commerciallyfrom Ticona, LLC) is initially heated to 120° C. and then powder coatedwith a pentaerythritol tetrastearate lubricant (Glycolube® P availablefrom Lonza, Inc.). Compound B and glass fibers are thereafter meltblended with the polymer so that the final composition contains 68.95wt. % liquid crystalline polymer, 0.3 wt. % lubricant, 30 wt. % glassfibers, and 0.75 wt. % of Compound B. Fiberglass is 3 mm chopped strandE glass with a 10 micron diameter (available from Nippon Electric GlassCo Ltd). The samples are melt-blended using a Coperion 32-mm co-rotatingfully intermeshing twin screw extruder having eleven (11) temperaturecontrol zones, including one at the extrusion die. The extruder has anoverall L/D of 40, with potential feed zones at an L/D of 1, 16, and 24;shear zones at an L/D of 12, 20, 28, and 32; and a degassing/vacuum zoneat an L/D of 36. The polymer pellets are fed at an L/D of 1 and theglass fibers are fed at an LID of 16 via a gravimetric feeder. CompoundB is fed at an L/D of 24. Following melt blending, the sample isquenched in a water bath to solidify and granulated in a pelletizer. Allcompositions are compounded at a rate of 140 pounds per hour, with abarrel temperature of 290° C. in the glass fiber mixing zone and a screwspeed of 450 RPM.

COMPARATIVE EXAMPLES 1-3

A sample is formed as described in Example 5 except that Compound B isnot employed (Comp. Ex. 1). Samples are also formed as described inExample 5 except that 4,4′-biphenol is employed rather than Compound B.More particularly, Comp. Ex. 2 involves feeding 4,4′-biphenol inconjunction with the polymer pellets (L/D of 1) and Comp. Ex. 3 involvesfeeding 4,4′-biphenol downstream of the glass fibers and polymer pellets(L/D of 24). The processing conditions for all of the examples aresummarized in the following table.

Example Comp. Comp. Comp. Ex. 1 Ex. 2 Ex. 3 5 L/D of Polymer Feed 1 1 11 L/D of Glass Fiber Feed 16 16 16 16 L/D of Compound B Feed — — — 24L/D of 4,4′-Biphenol Feed — 1 24 — Screw Speed 450 450 450 450Throughput Rate 140 140 140 140 Fiber mixing temperature (° C.) 290 290290 290 Torque (%) 32-34 34-36 34-35 32-35 Melt Temperature (° C.) 341339 341 340

Following formation, the compositions are dried for 3 hours at 120° C.and tested for melt viscosity at 350° C., which is included in the tablebelow. The pellets are thereafter injection molded to obtain specimensfor tensile, impact, flexural and deflection temperature under loadmeasurements as well as blister performance. All compositions areinjection molded at ISO 294 conditions. The pellets were first dried for3 hours at 120° C. The following conditions are used to mold the testspecimens: Barrel Temperature—315° C.; Mold Temperature—100° C.; BackPressure—50 psi; Hold Pressure—10,000 psi; Hold Pressure Time—5 sec;Cooling Time—25 sec; and Cycle Time—40 sec. The following table showsthe resulting thermal and mechanical properties.

Example Comp. Comp. Comp. Ex. 1 Ex. 2 Ex. 3 5 Ash (%) 29.6 29.9 29.629.7 Melt Viscosity (Pa-sec at 37.2 24.5 28.2 18.7 350° C. and 1000 s⁻¹)Melt Viscosity (Pa-sec 55.4 36.2 39.2 29.4 at 350° C. and 400 s⁻¹)Pellet Density (g/cc) 1.564 1.562 1.568 1.553 Density (%) 96.3 96.2 96.595.6 Melt Temperature (° C.) 333.2 333.4 332.8 331.8 Crystallinity 295.2294.1 294.8 287.4 Temperature (° C.) Blister Free 270 250 260 270Temperature (° C.) Tensile Strength (MPa) 165 143 150 164 TensileElongation (%) 1.72 1.55 1.49 2.04 Tensile Modulus (MPa) 16650 1395014550 16450 Flexural Strength (MPa) 230.57 204.21 212.32 232.95 FlexuralModulus (MPa) 17000 14950 15250 16600 Notched Charpy Impact 36 29 27 36Strength (kJ/m²) DTUL (° C.) 265 250 252 267 Peak Pressure to Fill 82607890 8300 6060 (psi) Maximum Load Point 11.1 11.5 10.6 10.9 (lb-f)Warpage Unaged - 0.913 0.955 0.904 0.905 LGA (mm) Warpage Aged - 2.4372.643 2.479 2.189 LGA (mm)

As indicated, when Compound B is fed downstream at 24 L/D (Example 5), asubstantial reduction in melt viscosity is also observed. Furthermore,Example 5 also exhibited excellent mechanical and thermal properties(e.g., BFT) due to the addition of Compound B after dispersion of theglass fibers. In contrast, the use of 4,4′-biphenol resulted in asubstantial reduction in mechanical properties, even when added afterfiber dispersion (Comp. Ex. 3).

These and other modifications and variations of the present inventionmay be practiced by those of ordinary skill in the art, withoutdeparting from the spirit and scope of the present invention. Inaddition, it should be understood that aspects of the variousembodiments may be interchanged both in whole or in part. Furthermore,those of ordinary skill in the art will appreciate that the foregoingdescription is by way of example only, and is not intended to limit theinvention so further described in such appended claims

What is claimed is:
 1. A thermotropic liquid crystalline polymercomposition comprising a liquid crystalline polymer and an aromaticamide oligomer having the following general formula (II):

wherein, X₁, X₂, and X₃ are independently C(O)HN or NHC(O); R₅, R₇, R₈,and R₉ independently selected from halo, haloalkyl, alkyl, alkenyl,alkynyl, aryl, heteroaryl, cycloalkyl, and heterocyclyl; m is from 0 to3; and p, q, and r are independently from 0 to
 5. 2. The polymercomposition of claim 1, wherein the liquid crystalline polymer is whollyaromatic.
 3. The polymer composition of claim 1, wherein the aromaticamide oligomer has a molecular weight of about 3,000 grams per mole orless.
 4. The polymer composition of claim 1, wherein the oligomer hasfrom 3 to 10 amide functional groups per molecule.
 5. The polymercomposition of claim 1, wherein m, p, q, and r are
 0. 6. The polymercomposition of claim 1, wherein m is 0, and p, q, and r areindependently from 1 to
 5. 7. The polymer composition of claim 6,wherein R₇, R₈, R₉, or combinations thereof are unsubstituted aryl,unsubstituted cycloalkyl, aryl substituted with and/or cycloalkylsubstituted with an amide group having the structure: —C(O)R₁₂N—or—NR₁₃C(O)—, wherein R₁₂ and R₁₃ are independently selected fromhydrogen, alkyl, alkenyl, aryl, heteroaryl, cycloalkyl, andheterocyclyl.
 8. The polymer composition of claim 7, wherein R₇, R₈, andR₉ are phenyl substituted with —C(O)HN—or —NHC(O)—.
 9. The polymercomposition of claim 1, wherein the oligomer is selected from the groupconsisting of the following compounds and combinations thereof:Structure Name

N1,N3,N5-triphenyl benzene-1,3,5- tricarboxamide

N1,N3,N5-tris(4- benzamidophenyl)benzene- 1,3,5-tricarboxamide

N1,N3,N5-tris(3-benzamidophenyl)benzene- 1,3,5-tricarboxamide


10. The polymer composition of claim 1, wherein the oligomer isN1,N3,N5-tris(4-benzamidophenyl)benzene-1,3,5-tricarboxamide.
 11. Thepolymer composition of claim 1, wherein the liquid crystalline polymeris a wholly aromatic polyester or polyesteramide.
 12. The polymercomposition of claim 1, wherein aromatic amide oligomers are employed inan amount of from about 0.1 to about 5 parts by weight relative to 100parts by weight of the liquid crystalline polymer.
 13. The polymercomposition of claim 1, wherein the ratio of the melt viscosity of theliquid crystalline polymer to the melt viscosity of the polymercomposition is at least about 1.1.
 14. The polymer composition of claim1, wherein the ratio of the melt viscosity of the liquid crystallinepolymer to the melt viscosity of the polymer composition is from about 3to about
 40. 15. A filled polymer composition comprising the polymercomposition of claim 1 and a filler material.
 16. The filled polymercomposition of claim 15, wherein the filler material comprises fibers, amineral filler, or a combination thereof.
 17. A molded articlecomprising the polymer composition of claim
 1. 18. A method for forminga thermotropic liquid crystalline polymer composition, the methodcomprising melt blending a liquid crystalline polymer and an aromaticamide oligomer having the following general formula (II):

wherein, X₁, X₂, and X₃ are independently C(O)HN or NHC(O); R₅, R₇, R₈,and R₉ are independently from halo, haloalkyl, alkyl, alkenyl, alkynyl,arl, heteroaryl, cycloalkyl, and heterocycly; m is from 0 to 3; and p,q, and r are independently from 0 to
 5. 19. The method of claim 18,wherein the liquid crystalline polymer is wholly aromatic.
 20. Themethod of claim 18, wherein the oligomer has a molecular weight of about3,000 grams per mole or less.
 21. The method of claim 18, wherein theoligomer has from 3 to 10 amide functional groups per molecule.
 22. Themethod of claim 18, further comprising blending a filler material withthe liquid crystalline polymer to form a filled composition.
 23. Themethod of claim 22, wherein the filler material comprises fibers, amineral filler, or a combination thereof.
 24. The method of claim 23,wherein the filler material is blended with the liquid crystal polymerprior to blending the aromatic amide oligomer with the liquid crystalpolymer.